1. Field of the Invention
The present invention relates to a tension release device, and more particularly to a tension release device for compensating mechanical error of a tension device for a sewing machine.
2. Description of the Prior Art
For the technology on the tension device used on a sewing machine to control the tension of the sewing thread and the tension release device for controlling the tension device, the applicant of this applicant has applied for a patent called “a control device used on a sewing machine capable of coaxially releasing the tension device and the pressure of the presser” and successfully got it approved. The characteristic of the applicant's prior patent is that a control handle for controlling lifting and lowering of the presser also controls a linkage of the tension device, so as to simultaneously control the lifting and lowering of the presser, as well as the tension of the thread. The linkage includes a swaying member to the tension device and sways in a two-dimensional fashion to push the top of the tension device, therefore, the accuracy of the motion of the linkage is limited. In addition, accumulation or abrasion caused error will occur after a certain time of period of use or after the tension device and the linkage are assembled together, and cannot be adjusted.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages.